1/*	$OpenBSD: select.h,v 1.17 2016/09/12 19:41:20 guenther Exp $	*/
2
3/*-
4 * Copyright (c) 1992, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 *	@(#)select.h	8.2 (Berkeley) 1/4/94
32 */
33
34#ifndef _SYS_SELECT_H_
35#define	_SYS_SELECT_H_
36
37#include <sys/types.h>
38
39#ifndef _TIMEVAL_DECLARED
40#define _TIMEVAL_DECLARED
41struct timeval {
42	time_t		tv_sec;		/* seconds */
43	suseconds_t	tv_usec;	/* and microseconds */
44};
45#endif
46
47#ifndef _TIMESPEC_DECLARED
48#define _TIMESPEC_DECLARED
49struct timespec {
50	time_t	tv_sec;		/* seconds */
51	long	tv_nsec;	/* and nanoseconds */
52};
53#endif
54
55/*
56 * Select uses bit masks of file descriptors in longs.  These macros
57 * manipulate such bit fields (the filesystem macros use chars).
58 * FD_SETSIZE may be defined by the user, but the default here should
59 * be enough for most uses.
60 */
61#ifndef	FD_SETSIZE
62#define	FD_SETSIZE	1024
63#endif
64
65/*
66 * We don't want to pollute the namespace with select(2) internals.
67 * Non-underscore versions are exposed later #if __BSD_VISIBLE
68 */
69#define	__NBBY	8				/* number of bits in a byte */
70typedef uint32_t __fd_mask;
71#define __NFDBITS ((unsigned)(sizeof(__fd_mask) * __NBBY)) /* bits per mask */
72#define	__howmany(x, y)	(((x) + ((y) - 1)) / (y))
73
74typedef	struct fd_set {
75	__fd_mask fds_bits[__howmany(FD_SETSIZE, __NFDBITS)];
76} fd_set;
77
78static __inline void
79__fd_set(int fd, fd_set *p)
80{
81	p->fds_bits[fd / __NFDBITS] |= (1U << (fd % __NFDBITS));
82}
83#define FD_SET(n, p)	__fd_set((n), (p))
84
85static __inline void
86__fd_clr(int fd, fd_set *p)
87{
88	p->fds_bits[fd / __NFDBITS] &= ~(1U << (fd % __NFDBITS));
89}
90#define FD_CLR(n, p)	__fd_clr((n), (p))
91
92static __inline int
93__fd_isset(int fd, const fd_set *p)
94{
95	return (p->fds_bits[fd / __NFDBITS] & (1U << (fd % __NFDBITS)));
96}
97#define FD_ISSET(n, p)	__fd_isset((n), (p))
98
99#if __BSD_VISIBLE
100#define	FD_COPY(f, t)	(void)(*(t) = *(f))
101#endif
102#define	FD_ZERO(p) do {					\
103	fd_set *_p = (p);				\
104	__size_t _n = __howmany(FD_SETSIZE, __NFDBITS);	\
105							\
106	while (_n > 0)					\
107		_p->fds_bits[--_n] = 0;			\
108} while (0)
109
110#if __BSD_VISIBLE
111#define	NBBY	__NBBY
112#define fd_mask	__fd_mask
113#define NFDBITS	__NFDBITS
114#ifndef howmany
115#define howmany(x, y)	__howmany(x, y)
116#endif
117#endif /* __BSD_VISIBLE */
118
119#ifndef _KERNEL
120#ifndef _SIGSET_T_DEFINED_
121#define _SIGSET_T_DEFINED_
122typedef unsigned int sigset_t;
123#endif
124
125#ifndef _SELECT_DEFINED_
126#define _SELECT_DEFINED_
127__BEGIN_DECLS
128int	select(int, fd_set * __restrict, fd_set * __restrict,
129	    fd_set * __restrict, struct timeval * __restrict);
130int	pselect(int, fd_set * __restrict, fd_set * __restrict,
131	    fd_set * __restrict, const struct timespec * __restrict,
132	    const sigset_t * __restrict);
133__END_DECLS
134#endif
135#endif /* !_KERNEL */
136
137#endif /* !_SYS_SELECT_H_ */
138